1. Field of the Invention
The present invention relates to an apparatus for recording by jetting a liquid for the recording such as an ink jet recording apparatus and, more particularly, to a liquid jet recording apparatus using a liquid for the recording such that a physical property value of its viscosity or the like varies in dependence upon ambient temperature.
2. Description of the Prior Art
Ink jet recording apparatus have advantages such that the direct recording is possible and the recording can be easily done using color inks and the recording can be performed without noise, and the like; therefore, they are being highlighted as new recording technology. Particularly, an ink jet recording apparatus of the on-demand system is becoming a principal technology among full color printer technologies that are recently highlighted from a viewpoint of its low cost and small dimensions.
On the other hand, physical property values of the viscosity and the like of the inks which are used as the recording liquids in these ink jet recording apparatuses easily vary in dependence upon ambient temperature. Therefore, when the physical property values of the recording inks change depending upon ambient temperature in this way, the ink emitting characteristics vary, so that this requires means for the temperature compensation of some types to preferably keep the recording quality irrespective of a change in ambient temperature.
For example, as will be described in detail hereinlater, in an ink jet recording apparatus of the on-demand system using, as an energy source for ink emission, a piezo transducer (hereinbelow, referred to as a piezo element) serving as an example of electrical-mechanical converting elements, it is necessary to refill the ink for the next emission in the head portion of the ink jet head, i.e., in the ink emitting orifice portion for the interval from the time when a necessary quantity of ink has been once emitted to the time when a next necessary quantity of ink is again emitted, and it takes a certain time (refilling time) to refill this ink. Consequently, to perform the recording without using the recording quality to deteriorate, it is necessary to set the time interval of the ink emission due to the driving of such a piezo element to be not shorter than this ink refilling time. Namely, otherwise the ink would have been emitted before a necessary quantity of ink is refilled in the ink emitting orifice portion, so that a quantity of ink to be emitted becomes less than a necessary quantity. Therefore, this invites undesirable situations such as deterioration of recording quality and non-emission of inks.
The refilling time of ink mentioned above depends upon the physical property values of viscosity and the like of inks and as the viscosity of ink increases, the time needed to refill becomes longer. On the other hand, the viscosity of ink depends upon ambient temperature and as the temperature is lower, there is a tendency such that the viscosity becomes larger. Therefore, the lower the ambient temperature is, the longer the time required to refill becomes.
Therefore, to always assure the good recording with high quality irrespective of a change in ambient temperature, for example, there has been considered a method whereby the recording speed to be determined by the ink emitting frequency which is a reciprocal number of the ink emitting time interval is preset in accordance with the ink refilling time under the lowest temperature to be presumed, or means for temperature compensation for keeping the ink temperature at constant by a heating apparatus such as a heater or the like. However, in the former method, since the recording speed has been unconditionally determined so that the recording apparatus is fitted for use under the lowest temperature to be presumed, this causes an inconvenience such that the recording time becomes unnecessarily longer when the recording apparatus is used under the conditions at ordinary to high temperatures. On one hand, in the latter method, there occurs an inconvenience such that the addition of a heating apparatus causes the recording apparatus to become large and the price to be raised.